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871.
872.
Hayato Tsurugi Akio Hayakawa Shun Kando Yoshitaka Sugino Kazushi Mashima 《Chemical science》2015,6(6):3434-3439
We developed a hydrodehalogenation reaction of polyhaloalkanes catalyzed by paddlewheel dimolybdenum complexes in combination with 1-methyl-3,6-bis(trimethylsilyl)-1,4-cyclohexadiene (MBTCD) as a non-toxic H-atom source as well as a salt-free reductant. A mixed-ligated dimolybdenum complex Mo2(OAc)2[CH(NAr)2]2 (3a, Ar = 4-MeOC6H4) having two acetates and two amidinates exhibited high catalytic activity in the presence of nBu4NCl, in which [nBu4N]2[Mo2{CH(NAr)2}2Cl4] (9a), derived by treating 3a with ClSiMe3 and nBu4NCl, was generated as a catalytically-active species in the hydrodehalogenation. All reaction processes, oxidation and reduction of the dimolybdenum complex, were clarified by control experiments, and the oxidized product, [nBu4N][Mo2{CH(NAr)2}2Cl4] (10a), was characterized by EPR and X-ray diffraction studies. Kinetic analysis of the hydrodehalogenation reaction as well as a deuterium-labelling experiment using MBTCD-d8 suggested that the H-abstraction was the rate-determining step for the catalytic reaction. 相似文献
873.
874.
An extended yield condition of soils applicable to the range of negative pressure is proposed. A closed surface is formulated in a simple mathematical form not limited to the range of positive pressure. A hardening function of plastic volumetric strain is adopted, based on the linear relation of both logarithms of volume and pressure extended to the negative range of pressure for the isotropic consolidation. Isotropic softening, due to the deviatoric plastic strain rate, and anisotropic hardening, due to rotation of yield surface (rotational hardening) are also incorporated into the extended yield condition. 相似文献
875.
Akio Yuchi Kouichi Mukaie Yuka Sotomura Hiromichi Yamada Hiroko Wada 《Analytical sciences》2002,18(5):575-577
The adsorption curves of divalent metal ions (M2+) to an iminodiacetate(IDA)-type chelating resin (-L2-) under the condition of metal ions in excess against IDA groups clearly indicated the difference in contribution between two species. Copper and nickel are adsorbed only as [(-L)M(II)], while cadmium and calcium are adsorbed as [(-L)M(II)] and [(-LH)2M(II)]. Addition of salts may enhance the deprotonation of IDA groups, interfere with the adsorption as [(-LH)2M(II)], and yield remarkable changes in adsorption curves, depending on the metal ions. 相似文献
876.
Yasuhiro Kobayashi Masaru Sakai Akio Ueda Kenichi Maruyama Toshiharu Saiki Koji Suzuki 《Analytical sciences》2008,24(5):571-576
This paper demonstrates a writing and reading methodology, which allows both to create and to detect sub-100-nm carboxyl-terminated patterns on light-transmissive quartz substrates by the same instrumental system. Such a technique, capable of creating carboxyl-terminated nanopatterns, offers several benefits for the miniaturization of biochips, since the carboxyl-terminated nanopatterns allow the easy immobilization of biomolecules by amide bond formation. As a consequence, increasingly miniaturized biochips require suitable analytical methods for the detection of nanopatterns. In our approach, carboxyl-terminated nanopatterns of down to 80 nm width were created using a photolabile silane coupling agent and a UV laser coupled to a near-field scanning optical microscope (NSOM). The same NSOM system was then used in a next step to detect the fabricated carboxyl-terminated nanopatterns after modification with a fluorescent label. Furthermore, as a first step towards biochip applications, the successful immobilization of several biomolecules, such as streptavidin, IgG and DNA on carboxyl-terminated nanopatterns was demonstrated. We have shown that our approach has the potential to lead to a new bioanalytical method, which enables one to write and to read biochips on a sub-100-nm scale by the same system. 相似文献
877.
We have developed efficient organic electroluminescent (EL) devices using a phosphorescent material, tris(2‐phenylpyridine) iridium, Ir(ppy)3, as an emitter material and a polymer buffer layer, tetraphenyldiamine‐containing poly(arylene ether sulfone) (PTPDES) doped with tris(4‐bromophenyl) aminium hexachloroantimonate (TBPAH) as an electron acceptor. In this device, a high external quantum efficiency of 21.6% and a luminous efficiency of 82 lm/W (77 cd/A) at 3.0 V were obtained. These high efficiencies can be explained by high quantum efficiency due to phosphorescent Ir(ppy)3 and high luminous efficiency realized by the use of the polymer buffer layer. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
878.
Kenshu Fujiwara Saori Yoshimoto Ayumi Takizawa Shin-ichiro Souma Hirofumi Mishima Akio Murai Hidetoshi Kawai Takanori Suzuki 《Tetrahedron letters》2005,46(40):6819-6822
Laurencin was efficiently synthesized from a C-glycoside derivative based on ring expansion of the oxane part of the starting compound into an eight-membered cyclic ether via a ring-cleavage/ring-closing olefin metathesis process, stereoselective introduction of a bromo group at C4, and convergent construction of the side-chain part using a lithiated enyne unit. 相似文献
879.
Daiyu Kondo Akio Kawabata Masahiro Horibe Mizuhisa Nihei Yuji Awano 《Superlattices and Microstructures》2003,34(3-6):389
We have succeeded in making peapod structures with vertically aligned multi-walled carbon nanotubes (MWNTs), grown on a silicon substrate using hot filament chemical vapor deposition. Opening the tips of the MWNTs was performed at 600 C using oxygen and then C60 molecules were deposited on them to fill their inner spaces. We confirmed that the MWNTs were open at the tips and filled with C60 molecules using transmission electron microscopy. In addition, it has been determined that MWNTs can be filled with other materials, such as molybdenum oxide. 相似文献
880.